Pharmacokinetics

Question 1

What are the 4 pharmacokinetic processes?

Answer 1

ADME

• Absorption
• Distribution
• Metabolism
• Excretion

Question 2

What are the 4 pharmacokinetic processes?

Answer 2

ADME

• Absorption
• Distribution
• Metabolism
• Excretion

Question 3

Polar drugs ____ readily cross the cell membrane

Answer 3

CANNOT

Question 4

Nonpolar drugs _____ readily cross the cell membrane

Answer 4

CAN

Question 5

What are 3 ways for drugs to cross the cell membrane?

Answer 5

1. Facilitated Diffusion - down gradient using channels
2. Active Transport - requires energy
3. Simple Diffusion - direct penetration of membrane

Question 6

What ways for drugs to cross the cell membrane are used mainly for ELIMINATION?

Answer 6

1. Facilitated Diffusion

2. Active Transport

Question 7

What ways for drugs to cross the cell membrane are used mainly for drugs to REACH their target tissues?

Answer 7

1. Simple Diffusion/direct penetration of the membrane

Question 8

What is an ex. of an active transporter that is mainly used to eliminate drugs from the cells?

Answer 8

P-glycoprotein (MDR1)

Question 9

The lower the pH, the ___ H+

Answer 9

More

Question 10

In what form can weak acids and weak bases cross cell membranes?

Answer 10

UNionized form

Question 11

Where do weak acids get trapped?

Answer 11

Trapped in Basic compartments

- cannot find an H+

Question 12

Where do weak bases get trapped?

Answer 12

Trapped in Acidic compartments

- cannot ditch an H+

Question 13

If drugs are bound to proteins in the blood, are they active?

Answer 13

NO - only active when free

Question 14

What type of drugs can freely cross the capillary?

Answer 14

Lipid-soluble

Question 15

Polar/Ionized drugs need what types of things in order to leave the capillary?

Answer 15

Transporters or pores in the capillary

Question 16

What is the major route of elimination for drugs?

Answer 16

Renal

Question 17

What are the 3 steps in Renal elimination and what drugs are eliminated?

Answer 17

1. Glomerular filtration - small free drugs
2. Passive tubular reabsorption - lipid soluble/unionized weak acids and bases
3. Active tubular secretion - protein bound drugs

Question 18

As you age, GFR ____

Answer 18

Decreases

Question 19

Mass eliminated per unit time

Answer 19

Excretion rate

- will increase as plasma [ ] increases

Question 20

Plasma volume from which all of solute is removed per unit time

Answer 20

Clearance

Question 21

Clearance is ____

Answer 21

Constant

Question 22

Tachyphylaxis

Answer 22

Rapid tolerance

Question 23

Drug physical dependence

Answer 23

Tolerance and withdrawal symptoms

Question 24

Drug-Drug interaction

Answer 24

1 drug either increases or decreases the effects of the other

Question 25

Idiosyncrasy

Answer 25

Unusual response to a drug due to an inherited enzyme defect

Question 26

Teratogenic

Answer 26

Drug causes abnormal fetal development | - Characteristic malformations that are dose dependent

Question 27

Adverse drug reactions are more common in what age group?

Answer 27

Elderly

Question 28

ex. of a teratogenic drug

Answer 28

Thalidomide | - small arms in children

Question 29

Drug-induced carcinogenesis may take years to appear. What drugs have the greatest carcinogenic potential?

Answer 29

Cancer chemotherapeutic drugs

Question 30

ex. of a drug that induces carcinogenesis

Answer 30

DES (diethylstilbestrol) | - Daughters had increased vaginal and uterine cancers

Question 31

Describe neonates albumin levels and blood brain barrier

Answer 31

Neonates albumin level = LOW - more free and active drug Neonates BBB = not fully developed - drugs can freely cross

Question 32

1-2 year old children metabolize drugs _____ than adults

Answer 32

FASTER

Question 33

Approximately how many patients will respond to a placebo?

Answer 33

1/3

Question 34

Zero-order kinetics

Answer 34

CONSTANT amount eliminated per unit time

Question 35

Drug elimination process is saturated in this type of kinetics

Answer 35

Zero-order

Question 36

With Zero-order kinetics, amount of drug eliminated is _____ of the drug concentration

Answer 36

Independent

Question 37

What is an example of a drug that uses Zero-order kinetics?

Answer 37

Ethanol | -- Constant amount eliminated per unit time

Question 38

1st-order kinetics

Answer 38

Constant FRACTION eliminated per unit time

Question 39

Drug elimination process that is not saturated in this type of kinetics

Answer 39

1st-order

Question 40

With 1st-order kinetics, amount of drug eliminated is ____ to the drug concentration

Answer 40

Directly related

Question 41

Which type of kinetics is the most common form of drug elimination?

Answer 41

1st-order kinetics

Question 42

In 5 half lives, what percentage of the drug will be eliminated?

Answer 42

97%

Question 43

Each half life backwards ____ the concentration

Answer 43

Doubles

Question 44

Capacity-limited reactions

Answer 44

Start as zero-order kinetics and then as concentrations fall transition to 1st-order kinetics

Question 45

Hockey stick like appearance

Answer 45

Capacity-limited reactions

Question 46

What is the loading dose?

Answer 46

Dose needed to rapidly achieve therapeutic drug concentration for drugs with long half lives

Question 47

What is an example of a drug that needs a loading dose?

Answer 47

Digoxin